Early in the Stargate program [or, episode 15 of Season 2] SG10 was assigned to study the planet P3W-451, which orbited a binary-star. One of the stars started to collapse. Major Henry Boyd, in charge of SG10, ordered his lieutenant to dial Earth. Back on Earth, the gate opened momentarily. When SG command tried to investigate by sending a MALP (Mobile Analytic Laboratory Probe) through the gate to P3W-451, they received an image of SG10. Major Boyd and his team appeared frozen in time though the image was a video feed. Captain Samantha Carter realized that the collapsing star had created a time dilation field. Not only would SG10 never reach the Stargate in time to save themselves, no one going through would ever be able to save them. P3W-451 and everything on it would get pulled into the black hole.
General Hammond and Captain Carter agreed there was nothing they can do to help SG10. Hammond ordered the disengagement with the wormhole. However, they could not shut it down, even after two attempts. Meanwhile, outside Cheyenne Mountain, Air Force Special Forces investigated the strange fact that guards outside the mountain lost contact with Stargate Command four hours earlier. It became apparent that the force of gravity from the black hole slowed down near the Stargate even on Earth’s side. Captain Carter determined that destroying the facility would not successfully disengage the connection to P3W-451. She theorized that the black hole’s gravity (causing the time dilation field) would slowly suck Stargate Command through the wormhole, then Cheyene Mountain, then Colorado, and eventually the Earth itself.
Carter devised an idea to use an explosion – but one directed through the Stargate – to give it enough of a power surge to jump the wormhole to another world. Then they could shut down the Stargate with ease. Colonel O’Neill and Colonel Cromwell (of the Special Forces team) rappelled “down” to the Stargate, where the gravity well had extended throughout the gate room. They intended to deliver a shaped charge to the Stargate but, as they struggled to hold on to place the bomb, the gravity well shattered the glass in the control room windows. The glass fell and a shard lodged onto Cromwell’s rope. Before O’Neill could arm the bomb, the gate’s metal iris collapsed, revealing the wormhole. This forced the two colonels and the bomb even closer to the Stargate. The glass shard cut through Cromwell’s rope, but O’Neill caught him. O’Neill managed to arm the bomb, but was unable to pull himself and Cromwell back up to safety. Teal’c went to assist them, but all three were pulled straight to P3W-451. The charge detonated as Carter predicted, saving Earth, but SG10 along with Cromwell, O’Neill, and Teal’c were lost.
Following this incident, Samantha Carter retired from the Stargate program.
Daniel Jackson, who was on PX3-808 when this happened, returned safely once the Stargate was back in proper working order. Jackson was instrumental in reassigning other personnel to form a new SG1 team. That, combined with the need to replace those lost from SG10 resulted in the restructuring of several SG teams. Due to the valuable contributions made by Teal’c, Dr. Jackson was determined to bring new, non-Earth consultants into the Stargate program. Dr. Jackson succeeded in convincing both the Tok’ra and Aschen to send consultants to work for the Stargate program. In the hopes of helping the off-worlders to better acclimate to their new working conditions, General Hammond originally assigned them to the same team, SG7. Although the members of SG7 have been working together for several months, the General has not yet considered reassigning either off-world teammate. He hopes that SG7’s NID member will have ample time to observe and appreciate the value of these particular consultants.